. >> it became more heated when a top republican chuck grassley clashed with chuck schumer. >> vice a particular the those pointing to the terrible tragedy in boston as an excuse for not doing a bill or delaying it. >> i ner said that. >> could never said you did. >> marco rubio said boston should have a bearing on the debate "if there are flaws in the immigration system that were exposed by the attack in boston, any immigration reform passed by congress this year should address those laws. meanwhile a letter sent today and kentucky republican rand paul wrote comic we should not proceed until we understand the specific failures of our immigration system. an interview with fox john boner said he d not see a need to delay the reform effort. >> it may actually help us to understand who is here and why they are here and what legal status they have. >> but said crews suggested the surest way to pass something is to narrow the focus. >> there is bipartisan agreement we have got to get serious about securing the border. likewise wide bipartisan agreement that we need to improve legal immigra